What we did and Why we did it:


Tree risk Assessment

During the span of this course all six groups had to do a tree assessment at all of their sites. These assessments were completed using the USDA Community Tree Evaluation Form. This form provided guidance for the groups along with standardization of their data. The trees that were observed were along the creek sites of each group. The point of this assessment is to identify issues that each tree might have that might lead to tree failure and hazards.

Methodology:

This study follows the methodology set forth by USDA Community Tree Evaluation guidelines. The ten trees that were selected to represent each site were within the sites reach. To determine a sites reach we measured from bank to bank and then multiplied that distance by 12. For example if it is 10 feet from bank to bank your reach will be 120 feet. Within this reach each group selected 10 trees that represent the area and not just the trees that are easy to get to. Trees Diameter at Breast Height were measures along with tree identification, location, defects and risk assessment.

The tree risk assessment returned a wide range of results that included a lot of very healthy trees. However it also contained several impaired trees that on paper look deceivingly stable. Many otherwise healthy and vigorous trees are being undercut buy stream bank erosion. If actions are not taken these trees will fail and no longer help hold the bank together. The mean tree risk vales for each site are shown in the following table. The range of scores is from 3 (perfect) to 12 (dire).


tree table.png Marsh Creek - Erosion at tree base.jpeg




Marsh Creek Trees



Long Island Creek Trees



Introduction | Stakeholders | Water Quality | Urban Ecology | Land Use Mapping | Study Sites | Methods | Results | Conclusions